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Servo Motor position control

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wdaehn
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Last seen: 4 months 2 weeks ago
Joined: 2017-09-12 17:26
Posts: 65
Servo Motor position control

Imagine you have a servo motor and want to drive to a given position, e.g. 10'000 steps forward. With the current vesc firmware this can be done. You turn on the speed control, use the Hall sensors for the position, ramp - using the positive ramping time - up to the Max ERPM until you have to slowly stop in order to hit the target position using the negative ramping time. And then our requested feature for the handbrake is responsible to stay at that point.

In addition the servo motor might have some slippage, so the motor observer cannot be trusted to know the exact position, it needs a secondary input. In my case another two Hall sensors on a wheel measuring the distance driven.

I would think there are a lot of use cases where supporting above out of the box would be very helpful. Servo motor, mine is a CableCam,....

Currently I have a CableCam controller based on a STM32F4 controlling the vesc for that purpose. Which I likely need anyhow but still.

https://github.com/wernerdaehn/CC3D-CableCam-Controller 

 

Note: Do not confuse this with the positional control built into the vesc as of today. The positional control at the moment is for angular movement. Obvious example: If you tell it to move 360° it does not move at all as it would end up at the same position.